Balancing a Telescope and mount using a Clamp meter

[Startrek]

Has anyone used an AC / DC clamp meter to balance their rig ?
An interesting concept and wonder if anyone else has thought of it ?
I just saw a YouTube clip from Cuiv the lazy geek on how to do it
Seems very accurate as it’s recording the current draw from the mounts RA and Dec motors on both sides of wings level.
He demonstrated the whole process and only took 10 or 15 minutes with very good balance. He was using a Skywatcher EQ6-R mount and looked like an 8”f4 newt
I suppose as long as the distance in movement up and down in Dec and Ra are similar then the resulting current difference in Amps should be accurate ( I’m assuming these little DC mount motors don’t have a big starting currents and lower run currents like AC motors do ) As soon as he moved the counterweights to a point where the current was equal or fairly close up and down , then the rig was balanced. He unlocked the clutches and proved both Ra and Dec were perfectly balanced

Comments welcome

[The_bluester]

I never thought of doing it that way. The issue would be that DC clamp meters can be fairly expensive. I have one I bought to set something up in my race car so I should give it a try. With the issues inherent to balancing an AZEQ6 RA axis when in EQ mode it would be really handy. With a patch loom you could do it with a normal DMM.

I was thinking about getting some spring scales to balance the force required to move it east and west of the pier but a current measurement might be more accurate.

[RyanJones]

I did think about this at one point but never actually tried it. A power box I made has a screen that shows current draw so I was going to use that but as I said, I never got around to it. I later questioned the need to do it. We balance our scopes marginally one side heavy anyway to reduce chatter in the worm drive so surely using gravitational balance is enough to get close then move the counter weights slightly in/out based on need. I guess it might have a better application on a newt where the focuser hasn’t been positioned downwards therefore causing a constant imbalance dependent on position. The current draw could be used to find the happy median maybe easier than gravitational balance ??? I’m not sure ??

Food for thought......

Ryan

[Alchemy]

Cuiv runs a really nice channel, he comes accross as very friendly and relaxed, maybe his system is better, but I do recall the USA spent a fortune making a pen that would work upside down in space.... the Russians took a pencil. Both worked but the pencil was way cheaper. Have fun either way.

[rbronca]

I use one of these to balance RA on my Skywatcher AZ-EQ6:
https://www.jaycar.com.au/600a-true-rms-ac-dc-clamp-meter/p/QM1632


Don't fall for the trap and get a cheaper AC only model. It wont work.



You must split the mount's figure 8 power lead a few cm and put only one conductor within the clamp.


The RA on these mounts is stiff and very tricky to balance by hand.

From there I move the weights a little either way to make sure the gears remain meshed and not float. East heavy of course.

I first found this method via Cuiv the lazy geek, like everyone else and it does really save time and allows you accurately balance the mount.



Having a multi meter in your kit is also handy for when you have power problems to track down. Adding clamp functionality is not eye wateringly more than a decent normal multimeter.